H.sub.2 -receptor antagonists (hereinafter referred to H.sub.2 -antagonists) are characterized as a family by their ability to inhibit the secretion of gastric acid. They are currently prescribed for the treatment of duodenal ulcers as well as other hypersecretory states. Prior to FDA approval of these compounds, the mainstay of therapy in the reduction of gastric acidity involved the neutralization of gastric acid with conventional antacids.
One of the chief complaints associated with administration of H.sub.2 -antagonists is their adverse taste and/or malodor. Many attempts have been made in developing delivery systems for these compounds with varying degrees of success.
U.S. Pat. No. 4,980,175 discloses an orally ingestible liquid composition for suspending therein high concentrations of at least one orally administrable pharmaceutically active agent. The composition is said to comprise
(a) about 40 to about 70 parts by weight of a member of the group consisting of at least one triglyceride or propylene glycol ester of a medium chain length alkanoic acid, wherein at least 95% by weight of the said acid has between 8 and 10 carbon atoms in the chain and at least one acetylated monoglyceride of at least one medium chain length alkanoic acid, having hydroxyl value of 0-15, an acetylation level of at least 95% and a melting point between about 4.degree. and about 12.degree. C.,
(b) about 2 to about 15 parts by weight of a polyglycerol ester, liquid at least 20.degree. C. and having an HLB of at least 8.0,
(c) about 1 to about 5 parts by weight of colloidal silicon dioxide to a total of between about 50 and about 90 parts by weight.
As stated above, the composition of U.S. Pat. No. 4,980,175 is said to permit fluid suspensions containing relatively high concentrations of pharmaceutically active agents. Disclosed therein are compositions of containing 20% by weight of calcium polycarbophil and 30% by weight of conventional antacids.
Surprisingly, it has been found that the suspension vehicle similar to that of U.S. Pat. No. 4,980,175 serves as a satisfactory vehicle for the administration of H.sub.2 -antagonists. The polyglycerol ester component of the fluid suspensions, disclosed as necessary in U.S. Pat. No. 4,980,175, may be omitted. When used in conjunction with H.sub.2 -antagonists as active components, such suspension vehicles function well in controlling the objectional taste and malodor of the active component. Further, the absence of the polyglycerol ester component required in the formulations of U.S. Pat. No. 4,980,175 has been found to also offer the benefits of (a) absence of the mildly objectional taste of the polyglycerol ester itself, and (b) the ability of the suspension to suspend additional quantities of active component.